Standard nutritional advice for irrigated sugarcane in South Africa and Swaziland is based on soil sample analysis and threshold values that have been determined experimentally over many years with surface-applied fertilisers. Fertilisers are normally applied in solid form during the early stages of crop development and watered in by the next irrigation cycle. The increasing popularity of subsu...

There is an increasing concern about agriculture’s role in polluting the environment which makes farmers feel guilty about using fertilizers. Fertigation is proposed as a panacea to this dilemma, which by this practice reaffirms the principles of 4Rs which are the right source, at the right rate, right time and right place. The aim of this study was to explore constraints and opportunities for ...

Israel is a small country with a total land area of 21,000 km, from which 20% is arable land. More than half of Israel has an arid to semi-arid climate. Approximately half of the cultivated area (200,000 hectares) has to be irrigated due to lack of rainfall and other water resources. Approximately 80% of the irrigated land in Israel uses the fertigation method, combining the application of wate...

The eye primordium of the moth, Manduca sexta, shows two different developmental responses to ecdysteroids depending on the concentration to which it is exposed. Tonic exposure to moderate levels of 20-hydroxyecdysone (20E) or its precursor, ecdysone, are required for progression of the morphogenetic furrow across the primordium. Proliferation, cell-type specification and organization of immatu...

Loss of function mutations of scabrous and conditional alleles of Notch and Delta affect the pattern of morphogenetic furrow development. By studying differentiation of R8 cells, the first photoreceptor neuron subtype to differentiate, we show that all furrow cells pass through an R8-competent stage. Function of Notch and scabrous is necessary if most of these cells are to attain other cell fat...

Morphogenesis involves the interplay of different cytoskeletal regulators. Investigating how they interact during a given morphogenetic event will help us understand animal development. Studies of ventral furrow formation, a morphogenetic event during Drosophila gastrulation, have identified a signaling pathway involving the G-protein Concertina (Cta) and the Rho activator RhoGEF2. Although the...

INTRODUCTION Contractile networks are fundamental to many cellular functions, particularly cytokinesis and cell motility. Contractile networks depend on myosin-II mechanochemistry to generate sliding force on the actin polymers. However, to be contractile, the networks must also be crosslinked by crosslinking proteins, and to change the shape of the cell, the network must be linked to the plasm...

soil infiltration characteristics affect the design, evaluation and management of furrow irrigation over afield. on the other hand, different variables influence furrow infiltration, making infiltration modeling for afield a complex process. this study was conducted to investigate the direct and indirect effects of allvariables affecting furrow infiltration. the blocked furrow method was used t...

*R. D. Lentz and D.L. Bjorneberg, USDA-ARS, Northwest Irrigation and Soils Research Lab., 3793 N. 3600 E., Kimberly, ID 83341 USA. *Corresponding author: [email protected] ABSTRACT For surface irrigation, the rate and spatial characteristics of infiltration processes influence crop productivity, water use efficiency, and erosion potential of stream flows. A change in infiltration rate a...